hi,
i want permutation for all alphabets with word length is 8.but i get only permutation for 4.pls help me to debug this issue
code:
<?PHP
FUNCTION permutations($letters,$num){
$last = STR_REPEAT($letters{0},$num);
$result = ARRAY();
WHILE($last != STR_REPEAT(lastchar($letters),$num)){
echo "$last";
$result[] = $last;
$last = char_add($letters,$last,$num-1);
}
$result[] = $last;
RETURN $result;
}
FUNCTION char_add($digits,$string,$char){
IF($string{$char} <> lastchar($digits)){
$string{$char} = $digits{STRPOS($digits,$string{$char})+1};
RETURN $string;
}ELSE{
$string = changeall($string,$digits{0},$char);
RETURN char_add($digits,$string,$char-1);
}
}
FUNCTION lastchar($string){
RETURN $string{STRLEN($string)-1};
}
FUNCTION changeall($string,$char,$start = 0,$end = 0){
IF($end == 0) $end = STRLEN($string)-1;
FOR($i=$start;$i<=$end;$i++){
$string{$i} = $char;
}
RETURN $string;
}
?>
<?php
for($j=1;$j<9;$j++){
$Array=permutations("ABCDEFGHIJKLMNOPQRSTUVWXYZ",$j);
FOR($i=0 ; $i < COUNT($Array) ; $i++) {
ECHO "$i." . $Array[$i] . "<BR>";
}
}
?>
output:
i want a output like this
a
b
c
d
e
f
.
.
.
.
.
z
aa
ab
ac
ad
.
.
.
.
.
.
az
.
.
.
.
.
.
.
.
.
.
zzzzzzzz
But the above code shown like this
a
b
c
d
.
.
.
.
.
aa
ab
ac
.
.
.
.
az
.
.
.
zzzz
yes
